National Research Institute for Earth Science and Disaster Resilience (NIED) has been conducting high sensitive seismic observation in the Kanto and Tokai regions since 1970”Ēs.
In the meanwhile, NIED has expanded the seismic network throughout Japanese Islands including the high-sensitivity seismograph network (Hi-net) in response to the devastation wrought by the Hyogo-ken Nanbu (Kobe) earthquake (M7.3) in 1995.
Hi-net has been under operation since 2000.
Their seismometers are installed at the bottom of a borehole at depths of over 100 m located about 800 stations nation-wide (with 20-25 km mesh).
These seismic data are open to the public through the website and are heavily used for earthquake research such as,
seismic observations used for earthquake monitoring by the Japan Meteorological Agency (JMA).
JUICE project has launched in 2013.
It is about time to revisit their precise earthquake locations because micro-earthquake records had been accumulating more than 10 years by Hi-net.
With these vast data from Hi-net and even more data from other organizations,
we relocated microseismic events by Double-Difference earthquake relocation method using both data,
phase picks and cross-correlation of waveforms, to build this JUICE catalog.
This catalog made possible for listing the precise relative earthquake locations in Japan.
Details of this catalog are now available in this article,

Hypocenters in this catalog are relocated using “relative” location method.
Please use the unified earthquake catalog of Japan by Japan Meteorological Agency (JMA) if “absolute” locations suit your needs.

Hypocenters in each grid space are processed independently from its neighboring grid space.
Seismicity on and around the edges of grid space may have artifact/virtual offset.
Please check the location of each grid space in your study region.
Please check our paper for more details.

Please cite our paper appropriately if you present any results using our data.

█ 3-D Hypocenter Distribution

The 3D hypocenter distribution (magnitude 1.5 or larger) of JUICE catalog
allows you to view from a variety of angles, rotate, and zoom in and out on
the web browser. You can check the local seismic activity, such as the
pattern along the known inland active fault, in this 3D graphics.

We, NIED, do not deliver any e-mails of immediate seismic information
obtained by the AQUA system.
In addition, please understand that we prohibit the redistribution
of the seismic data.
For more information, please read
How to use the Hi-net data and
FAQ.